Pump of variable resistance



Dec. 9, 1924- 1,518,833

C. ANDREINI v PUMP OF VARIABLE RESISTANCE Filed July l' 1922 2 Sheets-Sheet l l J7 38 4.5. 47 i 5%.@ .37-

, I 20 ian .f i 47 0 o 39 l l un mum Dec. 9, 1924. v 1,518,833

c. ANDRr-:INI

PUMP OF VARIABLE RESISTANCE Filed July 1. 1922 2 sheets-sheet 2' Z220@lil-0 2 C. jizz/@12e ma) Patented Dec. 9, 1924.

CORRADO ANDREINI,

PATENT OFFICE.

OF GROSSETO, ITALY.

:PUMP OF VARIABLE RESISTANCE.

Application ala July i,

To ZZ whom t may concern:

Be it known that I, CORRADO ANDREINI, a subject of the King of Italy, and residing at Grosseto, Italy, have invented certain new and useful Improvements in Pumps of Variable Resistance, of which the following is a specification.

In the usual types of pumps the operation is constant if the speed of thefpistons and the lift are constant. Consequently the latter require a constant driving power.

The object of this invention is to provide a pump in which a variable operation is effectedv by keeping the lift constant so that if the motor employed is of a variable power it is possible to utilize all the available power from a minimum to a predetermined maximum under the only condition that in correspondence of the variations of I-I. P. variations of the velocity of thev motor must take place within limited range.

The invention is especially useful on wind motors when used.

rIhe invention is clearly illustrated in the accompanying drawings, in which z- Fig. 1 is a vertical longitudinal section of the pump,

Fig. 2 is a vertical cross section thereof,

F ig. 3 is a horizontal section on the line 3 3 of Fig. 2,

Figs. 4 and 5 are enlarged elevational and section details respectively, and

Figs. 6 and 7 are enlarged elevational details partly in section of the equilibrated valve in different positions.

Referring now, more particularly, tothe accompanying drawings there is provided a suction and force pump with two identical cylinders and pistons having at every instant an equal movement in opposite directions, that is, when one moves upwardly the other moves downwardly at equal speed so that the volumes created by the movements thereof are always the same. The adoption of two cylinders instead of one has permitted besides the compensation of the volumes a smaller section of the pistons, equal disposition of the strain and the use of small air chambers. The pump consists of a carter 1 preferably of cast iron having in the lower part thereof two cylinders 2 in which the pistons 3 operate. The pistons are actu- 1922. Serial No. 572,162.

ated by the connecting rods 4 which in turn are coupled to the oscillating beam 5 mountedon an axle 6. The cylinders are joined together adjacent the front face thereof by a wall 7 and are likewise joined adjacent the rear face by another wall 8 being also connected at the medial portions thereof by a diaphragm 9 so that between the cylinders the walls 7 and S and the diaphragm 9 two separate chambers 10 and 11 are provided. The chamber 10 communicates with the chamber 11 through the porthole 13 and passageway 48 as well as the valve 14 while .the chamber 11 communicates with the chamber 12 in the base of the carter through portholes 14 and valve 22 and with the upper part of the carter through the equilibrated valve 15. By means of this arrangement the operation of the suction air chamber 11 is permitted even when the equilibrated valve 15 is open while the operation of the pump can even take place in the case of a very high lift.

p rThe carter 1 is closed by the cover 16 through which the axle 6 passes. A stuiiing box gland 17 prevents escape between the axle 6 and the cover 16. The chamber 10 is also provided with a flanged opened end 18 in which is insert-ed suction pipe 19 of the pump while the chamber 11 is provided with a hole through which the equilibrated valve 15 is arranged. The carter is provided at its upper portion with a flange 20 for the air chamber 21; The axle 6 is fitted with one of its ends into a support 22 preferably of bronze and fixed in turn on the carter by suitable fastening such as bolts.

It is preferred that the cylinders be formed of cast iron and integral with the carter and coated with bronze to prevent the formation of rust. It may also be noted that the suction valves 22 are provided with small guide rings and cones tofacilitate the flowing of water.

The pistons are fitted with a double leather packing 23 and with valves similar to the valves 22. and interchangeable with the same. The connecting rods are forked at opposite ends and are clamped by means of bolts 24 to the ends of the rocking beam 5 and the piston 3. rEhe rocking beam 5 is fixed in turn on the axle 6 by a wedge which the carter and that of the forcing coliunn in order that the -jflowing through hole .a with a delivery Q may take place out. of the foregoing formula it results that:

L h /L 22g 'from which it is deduced, ngAZQg being a constant valve and by putting:

and then the result hzcgz.

The load required to produce the variable delivery gf through the hole of the section A varies in direct proportion to the delivery square. This load that is in the carter and that of the forcing column and of the air chamber :2l is expressed in in. of water. By reducing to kg. each cm2 calling u the unit pressure) it results that or in other words mi l10.33

This difference of pression bears on every surface unit of the lower face of the piston 37 and therefore o being the area of the said face there will be a power upon it of:

that tries to cause a slight movement of the piston itself, but the piston will remain in the initial position until P ap that is P (weight of the piston): l-L-( However along with the increase of the velocity of the wind and in consequence of g, p rises in direct proportion so that after a certain time p will be greater than Pa. ln this event the piston 37 will be shifted upwardly. By this movement it uncovers another hole or opening and at the saine time it varies the inner angle of the rocking arin and lengthens the useful stroke of the piston to which a greater Lr corresponds. In this new position either the whole delivcry will pass under pression y) through the section of the uncovered holes so that the equation the speed of the motor and delivery of the pump are unbalanced so that the whole of this may pass through the uncovered holes P so that the pression will equal E or that work L7" results greater than Lm. ln this case the number of revolutions of the motor will be reduced thereby causing the diminution of the delivery and in consequence a pistons possible descent and a diminution in the useful stroke until equilibrium has been established. ln calculating the section of the holes it being; settled that the delivery of the pump shall be such as to absorb the different velocities of the wind, the whole motor power, the equilibrium will only be obtained when Lm is equal to Lr. ln the above stated description it been admitted that the ininiinun'i 'reke of the piston should be e ein. i csi' Vtivelv in the pump under cot on operated by the wind will at centrifugal force with a wheel of m. 1.60 diameter and in elevation corresponds te a. 3 in. wind), but to make sure that the equation Lmzl'i, should take place from the initial movement up to the time when the pump operates at full load then the following will occur. `Having fixed the velocity of the wind at which the wind motor starts there is nest fixed the available power the number of revolutions of the liy wheel, and in consequence the pistons average speed with such velocity of wind. f

Then the total upper elevation being given it follows that by putting the condition that the motor work should equal the resisting one and by fixing the theoretic delivery that the pump must have in order to absorb the whole power of the motor and the delive the pump would have at the saine speed for the whole stroke of the pist-ons.

This being stated from the proportion interoeding between strokes and deliv es it is easy to deduce the lena@ li of 'lie useiul stroke so that the equation limzliy should take place and then determine the inner angle of the oscillating arm which is given by the useful stroke as deterin' ied abone. As the weight in the water of the piston and connecting rod is known there is next Xed the area of the hole through which the water passes by velocity of the wind and by repeating the calculations for the velocit)r of the other winds, there is thusA determined the sections of the holes in the various positions of the piston 3l'.

Having attained the maximum stroke the annular segment 25 does not have to meet the roller 4:2 to cause the movement of the hand and the raising of the valve As a result the pump operates as an ordinary pump and the delivery thereof increases with the speed of rotation of the fly wheel but the latter cannot exceed an absolute maximum on account of the centrifugal force regulator of the motor. At this limit speed all the uncovered holes will leave free passage to the whole delivery under a xed weight or load. The valve l being equilibrated through the pressures existing in the carter does not hinder in any way the opening but the spring will have to ensure the perfect tightness under the sucking action that attempts to raise it from the seat. rlhere is never any great amount of strain. rlhe water having passed through the holes 36 in the cylinder flows into the air chamber 21 and thence up the ascending column 4A either directly or througl'i a reducing valve 45 if the upper elevation is strong.

In the case of very high lifts7 in the lower portion of the right hand cylinder, that is; the one on the side of the air chamber, there is provided a pipe which communicates with a small valve that opens auton'iatically by means of a contrivance like that described for the intermittent action of the oil vpump for a short while each 990 double movements vof the beam and it serves o restore theair into the air chamber, air which under strong pression has been dissolving in the water.

As the drawing shows the communieatingl tube between the carter and the chamber ll the continuation of the equilibrated valve is very short and the section thereof as well as the sections of passage through the valve and the portlioles of communication between the chambers 11 and 12 are such as to cause no material loss of load during the time the pump is idle.

'lhesuction air chamber besides avoiding water strokes during the opening of the equilibrated valve; prevents the freezing ,of water from injuring the pump which latter being syphon shaped is always primed independently of the suction and foot valves.

Having thus fully described the invention what is claimed as new and desired to be secured by Letters Patent is l. A variable resistance reciprocating pump having a pressure and a suction side; an equilibrated valve controlling a passage between the two sides of the pump; a spring normally holding the valve closed; valve operating means moving in synchronism with the pump; adjustable means forming an operating connection between the valve and the operating means; and means govi,5ie,eee

vchamber and passage connecting the two;

and check valve preventing baclnfiow from the intermediate chamber to the inlet chamber; and a. passage forming a communication between the intermediate chamber and the suction ends of the pump cylinders.v

3. A' variable resistance reciprocating pump constructed` as set forth iii claim 1 in which the operatii'ig connection lbetween the equilibrated valve and the operating means comprises a member movable by the governing means to different position to be contacted by the operating means at different parts of the pumps cycle of operation.

et. A variable resistance reciprocating pump constructed as set forth in claim l in which the governing means comprises a discharge conduit; a cylinder having one end open to the pressure side of the pump and extending into: the conduit and having openings in its wall at different points longitudinally thereof leading to the conduit; and a piston movable to uncover said holes.

5. A variable resistance reciprocating pump constructed as set forth in claim l in which the operating connection between the equilibrated valve and the operating means comprises a member movable by the governing means to'dill'erent positions to be'contacted by the operating means at different parts of the pumps cycle of operation; and the governing means comprises a discharge conduit; a cylinder having one end open to the pressure side of the pump and extending into the conduit and having' openings in its wall at different points longitudinally thereof leading to the conduit; and a piston movable to uncover said holes.

In testimony whereof l have hereunto signed my name in the presence of two witnesses:

CORRADO ANDRENI. Witnesses ELTON N. GAGE, J. RUTH. 

